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WSL2-Linux-Kernel
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mm: convert the rest to new page table lock api 

Only trivial cases left. Let's convert them altogether.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Alex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kirill A. Shutemov 2013-11-14 14:31:04 -08:00 коммит произвёл Linus Torvalds
Родитель cb900f4121
Коммит c4088ebdca
4 изменённых файлов: 73 добавлений и 59 удалений
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108
mm/huge_memory.c
Просмотреть файл

@ -710,6 +710,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
struct page *page)
{
pgtable_t pgtable;
spinlock_t *ptl;
VM_BUG_ON(!PageCompound(page));
pgtable = pte_alloc_one(mm, haddr);
@ -724,9 +725,9 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
*/
__SetPageUptodate(page);
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_none(*pmd))) {
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mem_cgroup_uncharge_page(page);
put_page(page);
pte_free(mm, pgtable);
@ -739,7 +740,7 @@ static int __do_huge_pmd_anonymous_page(struct mm_struct *mm,
set_pmd_at(mm, haddr, pmd, entry);
add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
atomic_long_inc(&mm->nr_ptes);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
}
return 0;
@ -759,6 +760,7 @@ static inline struct page *alloc_hugepage_vma(int defrag,
HPAGE_PMD_ORDER, vma, haddr, nd);
}
/* Caller must hold page table lock. */
static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
struct page *zero_page)
@ -790,6 +792,7 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
return VM_FAULT_OOM;
if (!(flags & FAULT_FLAG_WRITE) &&
transparent_hugepage_use_zero_page()) {
spinlock_t *ptl;
pgtable_t pgtable;
struct page *zero_page;
bool set;
@ -802,10 +805,10 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
count_vm_event(THP_FAULT_FALLBACK);
return VM_FAULT_FALLBACK;
}
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
set = set_huge_zero_page(pgtable, mm, vma, haddr, pmd,
zero_page);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
if (!set) {
pte_free(mm, pgtable);
put_huge_zero_page();
@ -838,6 +841,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
struct vm_area_struct *vma)
{
spinlock_t *dst_ptl, *src_ptl;
struct page *src_page;
pmd_t pmd;
pgtable_t pgtable;
@ -848,8 +852,9 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
if (unlikely(!pgtable))
goto out;
spin_lock(&dst_mm->page_table_lock);
spin_lock_nested(&src_mm->page_table_lock, SINGLE_DEPTH_NESTING);
dst_ptl = pmd_lock(dst_mm, dst_pmd);
src_ptl = pmd_lockptr(src_mm, src_pmd);
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
ret = -EAGAIN;
pmd = *src_pmd;
@ -858,7 +863,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
goto out_unlock;
}
/*
* mm->page_table_lock is enough to be sure that huge zero pmd is not
* When page table lock is held, the huge zero pmd should not be
* under splitting since we don't split the page itself, only pmd to
* a page table.
*/
@ -879,8 +884,8 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
}
if (unlikely(pmd_trans_splitting(pmd))) {
/* split huge page running from under us */
spin_unlock(&src_mm->page_table_lock);
spin_unlock(&dst_mm->page_table_lock);
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
pte_free(dst_mm, pgtable);
wait_split_huge_page(vma->anon_vma, src_pmd); /* src_vma */
@ -900,8 +905,8 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
ret = 0;
out_unlock:
spin_unlock(&src_mm->page_table_lock);
spin_unlock(&dst_mm->page_table_lock);
spin_unlock(src_ptl);
spin_unlock(dst_ptl);
out:
return ret;
}
@ -912,10 +917,11 @@ void huge_pmd_set_accessed(struct mm_struct *mm,
pmd_t *pmd, pmd_t orig_pmd,
int dirty)
{
spinlock_t *ptl;
pmd_t entry;
unsigned long haddr;
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, orig_pmd)))
goto unlock;
@ -925,13 +931,14 @@ void huge_pmd_set_accessed(struct mm_struct *mm,
update_mmu_cache_pmd(vma, address, pmd);
unlock:
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
}
static int do_huge_pmd_wp_zero_page_fallback(struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long address,
pmd_t *pmd, pmd_t orig_pmd, unsigned long haddr)
{
spinlock_t *ptl;
pgtable_t pgtable;
pmd_t _pmd;
struct page *page;
@ -958,7 +965,7 @@ static int do_huge_pmd_wp_zero_page_fallback(struct mm_struct *mm,
mmun_end = haddr + HPAGE_PMD_SIZE;
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, orig_pmd)))
goto out_free_page;
@ -985,7 +992,7 @@ static int do_huge_pmd_wp_zero_page_fallback(struct mm_struct *mm,
}
smp_wmb(); /* make pte visible before pmd */
pmd_populate(mm, pmd, pgtable);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
put_huge_zero_page();
inc_mm_counter(mm, MM_ANONPAGES);
@ -995,7 +1002,7 @@ static int do_huge_pmd_wp_zero_page_fallback(struct mm_struct *mm,
out:
return ret;
out_free_page:
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
mem_cgroup_uncharge_page(page);
put_page(page);
@ -1009,6 +1016,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
struct page *page,
unsigned long haddr)
{
spinlock_t *ptl;
pgtable_t pgtable;
pmd_t _pmd;
int ret = 0, i;
@ -1055,7 +1063,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
mmun_end = haddr + HPAGE_PMD_SIZE;
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, orig_pmd)))
goto out_free_pages;
VM_BUG_ON(!PageHead(page));
@ -1081,7 +1089,7 @@ static int do_huge_pmd_wp_page_fallback(struct mm_struct *mm,
smp_wmb(); /* make pte visible before pmd */
pmd_populate(mm, pmd, pgtable);
page_remove_rmap(page);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
@ -1092,7 +1100,7 @@ out:
return ret;
out_free_pages:
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
mem_cgroup_uncharge_start();
for (i = 0; i < HPAGE_PMD_NR; i++) {
@ -1107,17 +1115,19 @@ out_free_pages:
int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pmd_t *pmd, pmd_t orig_pmd)
{
spinlock_t *ptl;
int ret = 0;
struct page *page = NULL, *new_page;
unsigned long haddr;
unsigned long mmun_start; /* For mmu_notifiers */
unsigned long mmun_end; /* For mmu_notifiers */
ptl = pmd_lockptr(mm, pmd);
VM_BUG_ON(!vma->anon_vma);
haddr = address & HPAGE_PMD_MASK;
if (is_huge_zero_pmd(orig_pmd))
goto alloc;
spin_lock(&mm->page_table_lock);
spin_lock(ptl);
if (unlikely(!pmd_same(*pmd, orig_pmd)))
goto out_unlock;
@ -1133,7 +1143,7 @@ int do_huge_pmd_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
goto out_unlock;
}
get_page(page);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
alloc:
if (transparent_hugepage_enabled(vma) &&
!transparent_hugepage_debug_cow())
@ -1180,11 +1190,11 @@ alloc:
mmun_end = haddr + HPAGE_PMD_SIZE;
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
spin_lock(&mm->page_table_lock);
spin_lock(ptl);
if (page)
put_page(page);
if (unlikely(!pmd_same(*pmd, orig_pmd))) {
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mem_cgroup_uncharge_page(new_page);
put_page(new_page);
goto out_mn;
@ -1206,13 +1216,13 @@ alloc:
}
ret |= VM_FAULT_WRITE;
}
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
out_mn:
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
out:
return ret;
out_unlock:
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
return ret;
}
@ -1224,7 +1234,7 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
struct mm_struct *mm = vma->vm_mm;
struct page *page = NULL;
assert_spin_locked(&mm->page_table_lock);
assert_spin_locked(pmd_lockptr(mm, pmd));
if (flags & FOLL_WRITE && !pmd_write(*pmd))
goto out;
@ -1271,6 +1281,7 @@ out:
int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pmd_t pmd, pmd_t *pmdp)
{
spinlock_t *ptl;
struct anon_vma *anon_vma = NULL;
struct page *page;
unsigned long haddr = addr & HPAGE_PMD_MASK;
@ -1280,7 +1291,7 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
bool migrated = false;
int flags = 0;
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmdp);
if (unlikely(!pmd_same(pmd, *pmdp)))
goto out_unlock;
@ -1318,7 +1329,7 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
* relock and check_same as the page may no longer be mapped.
* As the fault is being retried, do not account for it.
*/
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
wait_on_page_locked(page);
page_nid = -1;
goto out;
@ -1326,13 +1337,13 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
/* Page is misplaced, serialise migrations and parallel THP splits */
get_page(page);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
if (!page_locked)
lock_page(page);
anon_vma = page_lock_anon_vma_read(page);
/* Confirm the PMD did not change while page_table_lock was released */
spin_lock(&mm->page_table_lock);
spin_lock(ptl);
if (unlikely(!pmd_same(pmd, *pmdp))) {
unlock_page(page);
put_page(page);
@ -1344,7 +1355,7 @@ int do_huge_pmd_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
* Migrate the THP to the requested node, returns with page unlocked
* and pmd_numa cleared.
*/
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
migrated = migrate_misplaced_transhuge_page(mm, vma,
pmdp, pmd, addr, page, target_nid);
if (migrated) {
@ -1361,7 +1372,7 @@ clear_pmdnuma:
update_mmu_cache_pmd(vma, addr, pmdp);
unlock_page(page);
out_unlock:
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
out:
if (anon_vma)
@ -2371,7 +2382,7 @@ static void collapse_huge_page(struct mm_struct *mm,
pte_t *pte;
pgtable_t pgtable;
struct page *new_page;
spinlock_t *ptl;
spinlock_t *pmd_ptl, *pte_ptl;
int isolated;
unsigned long hstart, hend;
unsigned long mmun_start; /* For mmu_notifiers */
@ -2414,12 +2425,12 @@ static void collapse_huge_page(struct mm_struct *mm,
anon_vma_lock_write(vma->anon_vma);
pte = pte_offset_map(pmd, address);
ptl = pte_lockptr(mm, pmd);
pte_ptl = pte_lockptr(mm, pmd);
mmun_start = address;
mmun_end = address + HPAGE_PMD_SIZE;
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
spin_lock(&mm->page_table_lock); /* probably unnecessary */
pmd_ptl = pmd_lock(mm, pmd); /* probably unnecessary */
/*
* After this gup_fast can't run anymore. This also removes
* any huge TLB entry from the CPU so we won't allow
@ -2427,16 +2438,16 @@ static void collapse_huge_page(struct mm_struct *mm,
* to avoid the risk of CPU bugs in that area.
*/
_pmd = pmdp_clear_flush(vma, address, pmd);
spin_unlock(&mm->page_table_lock);
spin_unlock(pmd_ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
spin_lock(ptl);
spin_lock(pte_ptl);
isolated = __collapse_huge_page_isolate(vma, address, pte);
spin_unlock(ptl);
spin_unlock(pte_ptl);
if (unlikely(!isolated)) {
pte_unmap(pte);
spin_lock(&mm->page_table_lock);
spin_lock(pmd_ptl);
BUG_ON(!pmd_none(*pmd));
/*
* We can only use set_pmd_at when establishing
@ -2444,7 +2455,7 @@ static void collapse_huge_page(struct mm_struct *mm,
* points to regular pagetables. Use pmd_populate for that
*/
pmd_populate(mm, pmd, pmd_pgtable(_pmd));
spin_unlock(&mm->page_table_lock);
spin_unlock(pmd_ptl);
anon_vma_unlock_write(vma->anon_vma);
goto out;
}
@ -2455,7 +2466,7 @@ static void collapse_huge_page(struct mm_struct *mm,
*/
anon_vma_unlock_write(vma->anon_vma);
__collapse_huge_page_copy(pte, new_page, vma, address, ptl);
__collapse_huge_page_copy(pte, new_page, vma, address, pte_ptl);
pte_unmap(pte);
__SetPageUptodate(new_page);
pgtable = pmd_pgtable(_pmd);
@ -2470,13 +2481,13 @@ static void collapse_huge_page(struct mm_struct *mm,
*/
smp_wmb();
spin_lock(&mm->page_table_lock);
spin_lock(pmd_ptl);
BUG_ON(!pmd_none(*pmd));
page_add_new_anon_rmap(new_page, vma, address);
pgtable_trans_huge_deposit(mm, pmd, pgtable);
set_pmd_at(mm, address, pmd, _pmd);
update_mmu_cache_pmd(vma, address, pmd);
spin_unlock(&mm->page_table_lock);
spin_unlock(pmd_ptl);
*hpage = NULL;
@ -2805,6 +2816,7 @@ static void __split_huge_zero_page_pmd(struct vm_area_struct *vma,
void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
pmd_t *pmd)
{
spinlock_t *ptl;
struct page *page;
struct mm_struct *mm = vma->vm_mm;
unsigned long haddr = address & HPAGE_PMD_MASK;
@ -2817,22 +2829,22 @@ void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
mmun_end = haddr + HPAGE_PMD_SIZE;
again:
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_trans_huge(*pmd))) {
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
return;
}
if (is_huge_zero_pmd(*pmd)) {
__split_huge_zero_page_pmd(vma, haddr, pmd);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
return;
}
page = pmd_page(*pmd);
VM_BUG_ON(!page_count(page));
get_page(page);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
split_huge_page(page);

13
mm/memory.c
Просмотреть файл

@ -550,6 +550,7 @@ void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *vma,
int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
pmd_t *pmd, unsigned long address)
{
spinlock_t *ptl;
pgtable_t new = pte_alloc_one(mm, address);
int wait_split_huge_page;
if (!new)
@ -570,7 +571,7 @@ int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
*/
smp_wmb(); /* Could be smp_wmb__xxx(before|after)_spin_lock */
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
wait_split_huge_page = 0;
if (likely(pmd_none(*pmd))) { /* Has another populated it ? */
atomic_long_inc(&mm->nr_ptes);
@ -578,7 +579,7 @@ int __pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
new = NULL;
} else if (unlikely(pmd_trans_splitting(*pmd)))
wait_split_huge_page = 1;
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
if (new)
pte_free(mm, new);
if (wait_split_huge_page)
@ -1516,20 +1517,20 @@ struct page *follow_page_mask(struct vm_area_struct *vma,
split_huge_page_pmd(vma, address, pmd);
goto split_fallthrough;
}
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (likely(pmd_trans_huge(*pmd))) {
if (unlikely(pmd_trans_splitting(*pmd))) {
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
wait_split_huge_page(vma->anon_vma, pmd);
} else {
page = follow_trans_huge_pmd(vma, address,
pmd, flags);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
*page_mask = HPAGE_PMD_NR - 1;
goto out;
}
} else
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
/* fall through */
}
split_fallthrough:

7
mm/migrate.c
Просмотреть файл

@ -1667,6 +1667,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
unsigned long address,
struct page *page, int node)
{
spinlock_t *ptl;
unsigned long haddr = address & HPAGE_PMD_MASK;
pg_data_t *pgdat = NODE_DATA(node);
int isolated = 0;
@ -1706,9 +1707,9 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
WARN_ON(PageLRU(new_page));
/* Recheck the target PMD */
spin_lock(&mm->page_table_lock);
ptl = pmd_lock(mm, pmd);
if (unlikely(!pmd_same(*pmd, entry))) {
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
/* Reverse changes made by migrate_page_copy() */
if (TestClearPageActive(new_page))
@ -1753,7 +1754,7 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
* before it's fully transferred to the new page.
*/
mem_cgroup_end_migration(memcg, page, new_page, true);
spin_unlock(&mm->page_table_lock);
spin_unlock(ptl);
unlock_page(new_page);
unlock_page(page);

4
mm/pgtable-generic.c
Просмотреть файл

@ -151,7 +151,7 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pgtable)
{
assert_spin_locked(&mm->page_table_lock);
assert_spin_locked(pmd_lockptr(mm, pmdp));
/* FIFO */
if (!pmd_huge_pte(mm, pmdp))
@ -170,7 +170,7 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
{
pgtable_t pgtable;
assert_spin_locked(&mm->page_table_lock);
assert_spin_locked(pmd_lockptr(mm, pmdp));
/* FIFO */
pgtable = pmd_huge_pte(mm, pmdp);